Method of and apparatus for rounding bristle ends



Dec. 5, 1967 G. s. CLEMENS 3,355,839

RISTLE ENDS METHOD OF AND APPARATUS FOR BOUNDING B 5 Sheets-Sheet 1 Filed NOV. l2, 1964 Imm INVENTOR.

Beal'ge Clemens, *Ze l Dec. 5, 1967 G, 5 CLEMENS' 3,355,839

METHOD OF AND APPARATUS FOR ROUNDING BRISTLE ENDS Filed Nov. l2, 1964 5 Shees-Sheet E Dec. 5, 1967 G. s. cLEML-:Ns

METHOD OF AND APPARATUS FOR ROUNDING BRISTLE ENDS 5 SheetsSheet 5 Filed Nov. 12, 1964 Dec. 5, 1967 G. s. CLEMENS METHOD OF AND APPARATUS FOR ROUNDING BRISTLE ENDS 5 Sheets-Sheet Filed Nov. l2, 1964 mun www um# Qgfr Dec. 5, 1967 G. s. CLEMENS 37355539 METHOD OF AND APPARATUS FOR ROUNDING BRISTLE ENDS Filed Nov. l2. 1964 5 Sheets-Sheet 5 United States Patent O 3,355,839 METHOD F AND APPARATUS FOR ROUNDING BRISTLE ENDS George S. Clemens, Northfield, Ill., assignor, by mesne assignments, to Carlson Tool & Machine Company, Geneva, Ill., a corporation of Illinois Filed Nov. 12, 1964, Ser. No. 410,394 23 Claims. (Cl. 51-56) ABSTRACT OF THE DISCLOSURE A bristle grinding method and apparatus for carrying out the method of rounding the ends of bristles by grinding the ends while retaining them in the form of a tuft wherein the individual bristles may have rotational and transverse movement within the tuft. The apparatus includes grinding surface elements which move in and out out of contact with the bristle ends while being rotated to effect the desired complex movement of the bristles in the tuft.

This invention relates to grinding and in particular to the grinding of ends of bristles such as for use in brushes.

In one form of brush, namely, a cosmetic brush, it is desirable to provide rounded ends on the bristles to prevent deleterious abrasion or scratching such as of the users scalp where the brush is a hair brush, or of a users gums as where the brush is a tooth brush. Heretofore, a common form of such a cosmetic brush was one wherein all of the bristles were trimmed in a single fiat plane permitting the grinding means to act concurrently against each of the bristle ends in that plane. However, in many modern more efficient designs of brushes, the brush shape is no longer planar, but rather rounded so that the ends of the bristles no longer lie in a single flat plane, thus, effectively precluding fully satisfactory grinding of the bristles after the bristles are secured in the brush heads.

The present invention is concerned with the grinding of bristle ends prior to the securing of the bristles in the brush head, thereby eliminating the problem discussed above. Heretofore, there has been a number of attempts to provide such a method of grinding the bristle ends. In one such method, the bristle tuft is retained in a holder, while a grinding surface comprising either a rotating or linear flow grinding surface is urged against the end of the tufts to simultaneously bend and grind them. This method, however, has proven unsatisfactory because of the nonuniformity of the grinding action therein. More specifically, the body of bristles in the tuft tends to support the outside bristles as the grinding surface is moving across the tuft, `while the outside bristles have no support when the grinding surface is moving away from the tuft. As a result, the bristles are effectively ground on one side only and form chisel shaped ends rather than round ends.

Thus, rather than solve the problem, the conventional known bristle grinding methods and apparatuses may aggravate the problem by providing a bristle end which has even more tendency to scratch the user.

The present invention comprehends an improved apparatus which is arranged to grind the bristle ends in the tuft prior to the time the tuft is installed in the brush head, yet which provides a substantially uniformly rounded end on each of the bristles of the tuft.

Thus, a principal object of the present invention is the provision of a new and improved method of rounding bristle ends.

A further object of the invention is the provision of a new and improved apparatus for rounding bristle ends.

Another object of the invention is the provision of such 3,355,839 Patented Dec. 5, i967 a method and apparatus for rounding the end of bristles in a tuft wherein each of the bristle ends is substantially uniformly rounded.

Yet another object of the invention is the provision of such a method and apparatus for rounding the end of bristles in a tuft wherein the tuft of bristles is loosely held substantially against axial movement while permitting rotational movement and transverse movement of the bristles relative to each other in the tuft, with grinding surface means for grinding an end of the bristles being moved seriatim against and away from the bristle ends while concurrently being moved transversely to the bristle ends for grinding the bristle ends while in contact therewith and causing movement of the bristles as a result of movement away from the grinding surface therefrom.

Still another object of the invention is the provision of such a method and apparatus wherein the movement of the grinding surface seriatim against and away from the bristle ends is at a high frequency for improved ecient bristle grinding.

A yet further object of the invention is the provision of such a method and apparatus wherein the means for effecting relative movement between the grinding surface and the bristle end is arranged to effect a rotational movement therebetween.

Yet another object of the invention is the provision of such a method and apparatus wherein a pair of grinding surfaces is provided for grinding concurrently the opposite ends of the bristles.

Still another object of the invention is the provision of such apparatus having new and improved means for holding the bristle tuft to provide the desired permitted rotation and movement of the bristles relative to each other in the tuft.

A yet further object of the invention is the provision of such an apparatus having new and improved means for facilitated grinding of a plurality of tufts concurrently by a single grinding surface.

Other objects and advantages of the invention will be apparent from the following description taken in connection with the accompanying drawing wherein:

FIGURE l is a front elevation of a 'bristle grinding apparatus embodying the invention, a portion of the drawing being broken away for facilitated illustration thereof;

FIGURE 2 is a vertical section thereof taken substantially along the line 2-2 of FIGURE 1;

FIGURE 3 is a fragmentary front elevation illustrating the grinding apparatus in an upper position in full lines and in an intermediate position in broken lines;

FIGURE 4 is a fragmentary enlarged vertical section taken substantially along the line 4 4 of FIGURE 3;

FIGURE 5 is a fragmentary enlarged horizontal section taken substantially along the line 5 5 of FIG- URE 3;

FIGURE 6 is a fragmentary enlarged vertical section taken substantially along the line 6 6 of FIGURE 3;

FIGURE 7 is a fragmentary enlarged vertical section taken substantially along the line 7 7 of FIGURE 2; and

FIGURE 8 is a fragmentary enlarged vertical section taken substantially along the line 8 8 of FIGURE 2.

As discussed briefly above, it is desirable to provide bristles in tufts with the ends of the bristles rounded. The present invention comprehends an improved method of grinding bristles in such tufts which provides the desired rounded ends in a simple and economical manner.

More specifically, the invention comprehends a method of grinding bristles including the steps of rstly, loosely holding a tuft ofbristles to be rounded to permit relative movement between the bristles in the tuft and rotation of the individual bristles about their respective axes. The ends of the bristles are engaged by a grinding surface means which is reciprocatively moved against the ends of the bristles in the direction of the axis thereof and moved away from the bristles after a short grinding engagement with the ends. This cycle of operation is repeated a large number of times at a relatively high rate.

In engaging the bristle ends by movement axially of the bristle, the tuft is compressed by the grinding surface means. Thus, when the grinding surface means is moved away from the bristle end, the strain forces in the bristles cause them to spring to their original configuration and in doing so effect a translation relative to each other and about their axes to provide the desired movement of the bristles within the tuft. Thus, when the grinding surface means again engages the bristle ends, the bristles are in a slightly different arrangement with different portions of the ends now engaged by the bristle grinding means so that a different portion of the bristle ends is ground during the next grinding cycle.

This operation is continued to perform a series of such successive grinding operations with the bristles translated slightly between each operation so as to result in uniformly rounded ends of the bristles in the tuft.

The invention further comprehends an -improved bristle grinding apparatus arranged to effect the bristle grinding steps discussed above in providing the desired rounded bristles.

In the exemplary embodiment of the invention as disclosed in the drawing, a bristle grinding apparatus generally designated is shown to comprise a front frame plate 11, a rear frame plate 12, and a front support 13, each upstanding from a base 14. Also mounted directly on the base 14 is an electric motor 15 which drives a shaft 16 by means of a motor pulley 17, a driven pulley 1S on shaft 16, and a` belt 19 extending between the pulleys.

As shown in FIGURE 2, the shaft 16 is rotatably journalled in bearings 2i) and 21 carried on front frame plate 11 and rear frame plate 12, respectively. The shaft 16 in turn is connected through a gear reduction mechanism 22 to a picker disc 23, a chain drive 24 to an orbital drive 25 for moving a pair of grinding plates 26 and 27 in an orbital path, and a cam drive 28 to a reciprocating mechanism 29 for reciprocating the grinding plates 26 and 27 toward and away from the opposite sides of the picker disc 23. A stock magazine 30 is provided for delivering bristles 31 to the picker disc which in the rotation thereof carries the bristles endwise between the grinding plates 26 and 27, as shown in FIGURE 5. As the bristles move in an arcuate path defined substantially by the circumference of the picker disc, they are successively engaged by the orbitally moving and concurrently reciprocated grinding plates 26 and 27 to effect a grinding, or rounding, of the opposite ends of the bristles projecting outwardly from the picker disc. The rounded bristles are removed from the picker disc into a discharge magazine 32 for use as desired.

The invention comprehends an improved arrangement of the bristle grinding apparatus 10 wherein the bristles are rounded uniformly about their ends in contradistinction to the chisel shaped bristles conventionally known in the apparatus. To this end, apparatus 10 is arranged to permit the individual bristles 31 to be picked in relatively loose tufts 33 in the disc 23 to permit rotation of the individual bristles about their longitudinal axes while being maintained against axial movement in the picker disc. At the same time, the loose retention of the bristles in the tufts 33 permits movement of the bristles transversely tio each other within the tuft. As a result of the rotation of the bristles about their respective axes and shifting around of the respective bristles within the tuft, the grinding action on the ends of the bristles is directed about the entire end of the bristle rather than against only one side thereof providing a uniformly rounded bristle end.

More specifically, the bristles, as shown in FIGURES 6 and 7, are retained in a tuft 33 having a generally circular configuration at the surface of the grinding plates 26 and 27. The bristles in the tuft 33 furthest from the axes of rotation of the grinding plates tend to be moved in the loose tuft at a greater speed, or in effect more positively, than the bristles closer to the axis of rotation. This causes a somewhat circular movement of the bristles in the tuft away from the perimeter generally through the center portion of the tuft and back outwardly to the portion of the tuft spaced furthest from the axis of rotation of the plates. This circulation of the bristles tends to thoroughly mix them and at the same time provide the desired rotation of the bristles about their own longitudinal axes so as to assure the desired rounding of the bristle ends as discussed above.

The rotation of the bristles about their respective axes and transverse movement thereof within the tuft is effected herein by the movement of the grinding plates as produced by the orbital drive 25 and the reciprocating mechanism 29. To provide improved high efficiency in this functioning, the cam drive 28 and reciprocating mechanism 29 are arranged to provide a high frequency of reciprocation as it appears that the rotation and translation of the bristles in the tuft are effected by the rapid disengagement of the grinding plates 26 and 27 `from the bristle ends after deflectively bearing against the bristles in the grinding operation. Illustratively, a frequency of 300 cycles per minute of such reciprocation has been found to provide a highly efficient bristle rounding operation.

Referring now more specifically to FIGURE 2 of the drawing, the gear reduction mechanism 22 is driven from shaft 16 by means of a belt 34, a driver pulley 35 on shaft 16, and a driven pulley 36 on a shaft 37 of the mechanism 22. As shown in FIGURE 8, the shaft 37 drives a reducer gear 38 in a gear box 39 which in turn drives an output shaft 40 carrying an output sprocket 41 connected by means of a chain 42 to a driven sprocket 43 carried on a picker disc shaft 44 rotatably journalled in a pair of bearings 45 carried by front frame plate 11 and rear frame plate 12. At its front end the shaft 44 carries a hub 46 on which is mounted the picker disc 23.

Referring now more specifically to FIGURE 7, the picker disc is provided at its periphery 47 with a plurality of circular slots 48 opening outwardly through the periphery 47 and adapted to receive bristles 31 from the supply magazine 30 as the bristles are urged downwardly through the magazine by suitable means such as weight 49. A stock fork 5() is mounted on a suitable bracket 51 carried by the front frame plate 11, by means of bolts 52 received in vertically elongated slots 53 in the fork 50 for facilitated picking of the bristles 31 by the slots 48. The stock fork 50 includes a finger portion 50a which, as shown in FIG- URE 7, is arranged to extend selectively chordally across the respective slots 48 during the lling operation so as to limit the number of bristles delivered to the slot in the tufts 33. Thus, as the picker disc 23 rotates beyond the stock fork finger 50a, the finger 50a no longer blocks a portion of the slot whereby the picked tufts are permitted to fill the entire slot in a loose fashion. As shown in FIG- URE 7, each of the supply magazine 30 and the collecting magazine 32 are mounted on the front frame plate 11 by a bracket 54.

As shown in FIGURES 1 and 3, a stock guide 55 is carried on a buffer housing 56 at the lower end of magazine 30, and a stock guide 57 is carried on a buffer housing 58 at the lower end of magazine 32 for engagement by the ends of the bristles 31 for maintaining the alignment of the bristles.

The bristles are retained in the slots 48 as they move around in the arcuate path defined by the periphery 47 of the picker disc by means of a buffer ring segment 59 extending approximately 300i degrees. The positioning of the buffer ring relative to the periphery 47 of the picker disc is adjusted by means of a pair of buffer ring clamps 61 and 62. As shown in FIGURE 2, the buffer ring clamps are mounted on posts 63 carried on the front frame plate 11.

The bristles are retained in the arcuate slots 48 as tufts 33 with their opposite ends extending outwardly from the slots as illustrated in FIGURE 5. After the bristles have been carried approximately 330 degrees from the picking position at the lower end of magazine 30, they engage a lower finger portion 64 on the magazine 32 which guides them out from the slots 48 and up into the magazine 32, leaving the slots 48 empty for picking up new bristles as the disc rotates beyond the magazine 32 back to the picking position at the bottom of magazine 30.

As discussed briefly above, the bristles in the tufts 33 are retained relatively loosely therein, weight 49 being preselected to provide the uniform packing of the bristles in the slot 48 at the lower end of the delivery magazine 30. As the bristles are carried in the arcuate path defined by the periphery 47 of the picker disc, their opposite ends are repeatedly engaged by the grinding plates 26 and 27 which as discussed briefly above are brought toward and away from the picker disc by means of the cam mechanism 28 and reciprocating mechanism 29 while the grinding plates are concurrently moved in an orbital path by the mechanism 25. More specifically, a shaft 66 is journalled at one end in a bearing 67 and is mounted at its opposite end in a hub 68 which, as shown in FIGURE 5, is rotatively mounted on front frame plate 11 by means of an annular slide ring 69. The shaft is rotated by means of a sprocket 70 driven `by a chain 71 from a sprocket 72 fixed to the drive shaft 16. A second shaft 73 is fixed to each of hubs 67 and 68 for rotation therewith about the axis of shaft 66 whereby the shaft 73 moves through a circular orbital path. Shaft 73 is permitted to rotate freely in the hub 68 by means of a sleeve bearing 74.

Referring more specifically to F IGURES 4 and 5, grinding plate 26 is provided with an annular support 75 carrying a sleeve bearing 76 in which shaft 73 is journalled, and grinding plate 27 is provided with an annular support 77 carrying a sleeve bearing 78 in which the outboard end of the shaft 73 is journalled. A fork 79 is secured to shaft 73 by a split clamp connector 80 and slidably receives a slide roller 81 secured to the support 75 by a bolt 82. Thus, the connection of the shaft 73 through the collar S0 and fork 79 to the support 75 causes the shaft 73 to rotate in the sleeve bearing 74 as the shaft is carried in the circular orbital path about the axis of shaft 66 so that in effect shaft 73 is prevented from rotating about its axis during the orbital movement. As shown in FIGURES 1 and 3, the annular supports 75 and 77 may be secured to the respective grinding plates by suitable means such as screws 84.

As best seen in FIGURE 5, the driving of the grinding plates 26 and 27 in the circular orbital path is effected in apparatus by means of a pair of mechanisms, such as mechanism 25, one at each end of the grinding plates. Thus, a second mechanism 25 is provided which is identical to mechanism 25 in all respects and driven in timed synchronization with mechanism 25 so as to move the entire grinding plates 26 and 27 in the same circular movement as followed by the orbitally revolved shaft 73. The elements of mechanism 25 are designated with the same numerals as applied against the elements of mechanism 25 except with the prime suffix, and no further description of the elements or the association thereof need -be provided herein.

As indicated briefiy above, the reciprocation of the grinding plates 26 and 27 toward and from the disc 23 is effected by means of a cam device 28. More specifically, cam device 28 includes an eccentric cam 85 secured to one end of shaft 16 by a suitable hub 86. The cam engages a follower 87 carried on a guide 88 adjustably secured by means of a screw 89 to the lower end of a shaft 90 having a` connector 91 at its upper end provided with a pin 92 received in a slot 93 of a first L-shaped arm 94 and a slot 95 of a second L-shaped arm 96. Arm 94 is pivotally mounted on a bracket 97 fixed to the upright 13, by means of a pivot pin 98 and arm 96 is pivotally mounted on bracket 97 by means of a pivot pin 99. The distal end of the L-shaped arm 94 is provided with a slot 100 receiving a pin 101 carried by a stub shaft 102, and the distal end of the arm 96 is provided with a slot 103 receiving a pin 104 carried by a stub shaft 105. As shown in FIGURE 6, the stub shaft 102 is slidably carried in a sleeve bearing 106 carried in a bearing retainer 107 secured to the front frame plate 11 as` by screws 108, and the stub shaft 105 is slidably carried in a bearing 109 carried by the upright 13. Each of the stu-b shafts is further axially slidable through the respective bearings 106 and 109 as a result of the movement of the distal ends of the arms 94 and 96 toward and away from each other, as illustrated in the full line and broken line showing in FIGURE 6, which movement is effected by the up and down movement of the connector 91 at the upper end ot the shaft 90 resulting from the operation of cam 85 on follower 87. The axial reciprocal movement of the stub shafts 102 and 105 is transmitted to the respective grinding plates 26 and 27 by means of a pair of connectors 110 and 111, respectively. Connector 110 is axially fixed but rotatively connected to the stub shaft 102 by connecting device 112, and connector 111 is axially fixed but rotatively connected to the stub shaft 105 by a similar connecting device 113. Connector 110 is provided with an arm 114 having a pin 115 fixedly secured to the grinding plate 26 journalled therein, and connector 111 is provided with an arm 116 having a pin 117 fixed to the grinding plate 27 journalled therein.

Thus, as the grinding plates describe the circular orbit produced by the shafts 73 and 73', the arms 114 and 116 rotate with the pins 115 and 117 describing an orbital path equal to the orbital path of the shafts 73 and 73', while the axes of the stub shafts 102 and 105 remain fixed. Thus, at any time during the orbital movement of the grinding plates 26 and 27, a concurrent movement toward and away from the picker disc 23 may be effected by the actuation of the arms 94 and 96 to move the stub shafts 102 and '105 axially as discussed above. To round the bristles at high efficiency, it is desirable to effect the reciprocation of the grinding plates at a relatively high rate such as 300 times per minute. However, the rounding of the bristles is effected at lower rates, although at somewhat decreased production efficiency.

It has been found that a grinding time of approximately 30 to 90 seconds provides a highly efficient operation. Thus, in the illustrative embodiment, the picker disc 23 is rotated at a preselected speed in the range of approximately 1 to 1/3 r.p.m. Illustratively, the picker disc 23 may have a diameter of approximately 18 inches and a thickness of 1/2 inch with the arcuate slots 48 comprising 3A; inch diameter holes spaced on 'Ma inch centers along the periphery 47 of the disc. The opening of the slots 48 into the periphery 47 may be approximately 1A inch. The difference inthe total length of the bristles 31 and the maximum spacing between the grinding plates 26 and 27, referred to as the bristle clearance, is preferably in the range of approximately l@ to "/32 inch. The clearance should be sufficiently large to prevent shifting of the bristles in the slot 4S, while at the same time should be small enough to prevent substantial loss in usable grinding time.

In the illustrated embodiment, the arms 94 and 96 are preferably arranged4 so that the pin 92 is spaced from the pivots 98 and 99, the same distance that the pins 101 and 104 are spaced therefrom so that with a cam rise of approximately .27 inch a maximum compression of the bristles between the plates of approximately .540 inc-h is effected. An eccentric radius, or spacing, of the shafts 73 and 73 from the shafts 66 and 66 of approximately 11A. inch has proven highly successfully as providing relatively high grinding efficiency while effectively avoiding excessive vibration. The grit characteristics of the grinding plates 26 and 27 may be varied over the grinding surface thereof so as to provide a relatively rough grinding during the initial portion of lthe grinding operation, and a smoother grinding during the last portion of the travel of the bristles between the plates. Illustratively a 240-grit size may be employed on the left portion of the grinding plates, as seen in FIGURE 3, whereas a 320-grit size may be employed on the right portion.

The picker load may be preselected to provide the desired loose retention of the Ibristles in the slot 48. Herein, the apparatus is arranged to have a picker load of between approximately 8 and 16. The term picker load is defined as the number of bristles withdrawn from a full tuft and, thus, is a measure of the fullness of each tuft. It has been found that where the picker load is above 8, i.e., with .02 inch bristles in a 3A; inch diameter slot, motility of the tufts as to the desired transverse movement is overly restricted, whereas in tufts wherein the picker load is below 16 the tufts tend to twist and lock in the slots.

To provide improved efficiency of transverse movement and rotation of the tufts about their axes in the picker disc during the repetitive grinding cycles, it is desirable to polish the picker disc slots, although it is preferable not to chamfer the edges thereof by more than .005 inch radius breaks.

The grinding plates 26 and 27 are preferably accurately parallel to the picker disc 23 so as to avoid shift of the tufts 33 therein during the grinding operation. The grinding plates 26 and 27 are preferably provided with a pair of guide plates 120, each having a lower portion 121 connected to the grinding plate and extending iat an angle of approximately 10 degrees therefrom. The reciprocation of the grinding plates, providing the desired orbital grinding action is preferably at relatively high rates such as at least 100 times per minute, the guide plates 120 facilitating the `grinding operation at such rates.

Thus, apparatus 10 provides an improved bristle rounding apparatus providing efficiently and economically bristles having uniformly rounded ends for use in brushes, such as hair brushes, and tooth brushes, and permitting the bristles to be installed on the brush backs so as to provide non-planar brushing surfaces of any desired configuration. The apparatus 10 is itself relatively simple and inexpensive, while yet providing the highly desirable bristle rounding functioning in an improved `and simplied manner.

While I have shown and described one embodiment of my invention, it is to be understood that it is capable of many modifications. Changes, therefore, in the construe` tion and arrangememnt may be made Without departing from the spirit and scope of the invention as defined in the appended claims.

I claim: 1. Apparatus for rounding the ends of bundled elongated elements comprising:

means for providing a supply of elongated elements to a picking zone;

means movable through said picking zone for segregation and loosely holding a bundle of a plurality of said elongated elements while permitting rotational movement and transverse movement of the elements relative to each other in the bundle;

grinding surface means for grinding an end of the elements; and means for moving said grinding surface means seriatim against and away from the elongated element ends while concurrently effecting relative movement between said surface and said elements and transversely to the element ends for grinding lthe element ends while in contact therewith and causing movement of the elements as a result of disengagement of the grinding surface therefrom.

2. The apparatus of claim 1 wherein said elongated elements comprise bristles and said bundle comprises a tuft of said bristles.

3. rl`he apparatus of claim 2 wherein said holding means is arranged to hold a plurality of bristle tufts for concurrent grinding by said grinding surface means.

4. The apparatus of claim 2 wherein said grinding surface means is arranged for grinding each of the opposite ends of the bristles.

5. The apparatus of claim 2 wherein said grinding surface means is arranged concurrently for grinding each of the opposite ends of the bristles.

6. The apparatus of claim 2 wherein said moving means is arranged to move said grinding means in a circular orbit.

7. The apparatus of claim 2 wherein said moving means is arranged to move the grinding surface means against and away from the bristle ends at least approximately times per minute.

8. The apparatus of claim 2 wherein said holding means comprises a member having a slot for holding the bristles with the ends thereof extending substantially outwardly from the member.

9. The apparatus of claim 2 wherein said holding means comprises a plate provided with a segmentally circular slot, said plate having a thickness substantially less than the length of said bristles for holding the bristles with the bristle ends extending substantially from said plate.

1G. The apparatus of claim 2 wherein said holding means comprises a member having a polished slot for holding the bristles with the ends thereof extending substantially outwardly from the member.

11. The apparatus of claim 2 wherein said holding means comprises a disc having a slot for holding the bristles with the ends thereof extending substantially outwardly from the disc, and means for rotating the disc to revolve said slot in a circular path parallel to said grinding surface means.

12. The apparatus of claim 2 wherein said grinding surface means comprises a plate and said moving means includes a pair of members supporting said plate at spaced portions thereof, said members being driven in circular orbits of substantially identical radius.

13. Apparatus for rounding the ends of bristles in a tuft, comprising:

a member having a slot for loosely holding a plurality of bristles in a tuft substantially against axial movement while permitting rotational movement and transverse movement of the bristles relative to each ther in the tuft, said slot having a preselected picker load delivery means for delivering to said slot a tuft of bristles having said preselected picker load; grinding surface means for grinding an end of the bristle; and

moving means for moving said grinding surface means seriatim against and away from the bristle ends while concurrently moving said surface transversely to the bristle ends for grinding the bristle ends while in contact therewith and causing movement of the bristles as a result of disengagement of the grinding surface therefrom.

14. The apparatus of claim 13 wherein said delivery means includes a stock fork disposed adjustably adjacent said slot for controlling the picker load.

15. Apparatus for rounding the ends of bristles in a tuft, comprising:

holding means for loosely holding a plurality of bristles in a tuft substantially against axial movement while permitting rotational movement and transverse movement of the bristles relative to each other in the tuft;

grinding surface means for grinding an end of the bristle;

guiding means on said grinding surface means for guiding the bristles to extend from said holding means a preselected distance; and

moving means for moving said grinding surface means seriatim against and away from the bristle ends while concurrently moving said surface transversely to the bristle ends for grinding the bristle ends while in contact therewith and causing movement of the bristles as a result of disengagement of the grinding surface therefrom. 16. Apparatus for rounding the ends of bristles in a tuft, comprising:

holding means for loosely holding a plurality of bristles in a tuft substantially against axial movement while permitting rotational movement and transverse movement of the bristles relative to each other in the tuft; grinding surface means for grinding an end of the bristle; moving means for moving said grinding surface means seriatim against and away from the bristle ends while concurrently moving said surface transversely to the bristle ends for grinding the bristle ends while in contact therewith and causing movement of the bristles as a result of disengagement of the grinding surface therefrom; and means for removing the ground bristles from said holding means including means for guiding the bristles to extend accurately from said holding means subsequent to the grinding thereof. 17. The method of rounding the ends of bristles in a tutt, comprising the steps of:

loosely holding a tuft of `bristles substantially against axial movement; moving a grinding surface axially to the bristles in seriatim against and away from the ends of the bristles for causing rotational movement and transverse movement of the bristles relative to each other in the tuft; and grinding the ends of the bristles while said bristles are being so moved. 18. The method of rounding the ends of bristles in a tuft, comprising the steps of:

loosely holding a tuft of bristles substantially against axial movement; and concurrently grinding the ends of the bristles and moving a grinding surface axially of the bristles in seriatim against and away from the ends of the bristles for causing rotational movement and transverse movement of the bristles relative to each other in the tuft. 19. The method of rounding the ends of bristles in a tuft, comprising the steps of:

loosely holding a tuft of bristles substantially against axial movement; and concurrently grinding the opposite ends of the `bristles and moving a grinding surface axially of the bristles in seriatim against and away from the ends of the bristles for causing rotational movement and transverse movement of the bristles relative to each other in said tuft. 20. The method of rounding the ends of bristles in a tuft, comprising the steps of:

loosely holding a tuft of bristles substantially against axial movement; and seriatim releasing and grinding the ends of the bristles at a rate of at least approximately times per minute. 21. The method of rounding the ends of bristles in a tuft, comprising the steps of:

loosely holding a tuft of bristles substantially against axial movement; and moving a grinding surface axially of the bristles in seriatim against and away from the ends of the bristles for causing rotational movement and transverse movement of the bristles relative to each other in the tuft to mix the bristles in said tuft, and grinding the ends of the so moved bristles. 22. The method of rounding the ends of bristles in a tuft, comprising the steps of:

loosely holding a tuft of `bristles substantially against axial movement; and

moving a grinding surface means seriatim axially of` the bristles against the ends of the bristles and away from the ends of the bristles while concurrently moving the grinding surface means transversely to the axes of the bristles to grind the ends of the bristles when the grinding surface means is in engagement therewith and cause rotational ymovement and transverse movement of the bristles relative to each other in the tuft upon movement of the grinding surface means away from the ends of the bristles. 23. The method of rounding the ends of bristles in a tuft of claim 22 wherein the grinding surface means is reciprocated against the ends of the bristles at a rate of at least approximately 100 times per minute.

References Cited UNITED STATES PATENTS 598,536 2/1898 Rodd 51-118 622,554 4/1899 Smith 51-6 1,495,747 5/1924 Izawa 51--281 2,669,075 2/ 1954 Dreyfus 51-145 2,700,259 1/ 1955 Dreyfus 51-119 XR 2,854,797 10/1958 Van Clief 51-112 X 3,063,204 11/1962 Baumgartner 51-119 HAROLD D. WHITEHEAD, Primary Examiner. 

1. APPARATUS FOR ROUNDING THE ENDS OF BUNDLED ELONGATED ELEMENTS COMPRISING: MEANS FOR PROVIDING A SUPPLY OF ELONGATED ELEMENTS TO A PICKING ZONE; MEANS MOVABLE THROUGH SAID PICKING ZONE FOR SEGREGATION AND LOOSELY HOLDING A BUNDLE OF A PLURALITY OF SAID ELONGATED ELEMENTS WHILE PERMITTING ROTATIONAL MOVEMENT AND TRANSVERSE MOVEMENT OF THE ELEMENTS RELATIVE TO EACH OTHER IN THE BUNDLE GRINDING SURFACE MEANS FOR GRINDING AN END OF THE ELEMENTS; AND MEANS FOR MOVING SAID GRINDING SURFACE MEANS SERIATIM AGAINST AND AWAY FROM THE ELONGATED ELEMENT ENDS WHILE CONCURRENTLY EFFECTING RELATIVE MOVEMENT BETWEEN SAID SURFACE AND SAID ELEMENTS AND TRANSVERSELY TO THE ELEMENT ENDS FOR GRINDING THE ELEMENT ENDS WHILE IN CONTACT THEREWITH AND CAUSING MOVEMENT OF THE ELEMENTS AS A RESULT OF DISENGAGEMENT OF THE GRINDING SURFACE THEREFROM. 